The clinicalpathological findings in a 32-year old woman with ataxia-telangiectasia are presented. This is the oldest patient with this disease to be studied thoroughly clinically and at autopsy. Multiple small gliovascular malformations in the brain and spinal cord and telangiectasis of the liver were found. Other advanced lesions of ataxia-telangiectasia are illustrated. The vascular malformations of the central nervous system and liver are unique. The patient died of a malignant lymphoproliferative disorder and had five other malignant and benign neoplasms.